Calling methods and systems for video phone

ABSTRACT

A calling method for the video phone, includes: playing a Multimedia Ring Back Tone for a calling terminal via a first bearer of video phone established between a Multimedia Ring Back Tone server and the calling terminal; establishing a second bearer of video phone between a called terminal and the Multimedia Ring Back Tone server upon detecting that the called terminal answers the call; and performing a video phone communication between the calling terminal and the called terminal via the first bearer and the second bearer established. Another calling method for the video phone, comprises: playing a Multimedia Ring Back Tone for the calling terminal by the Multimedia Ring Back Tone server via a third bearer of video phone established with the calling terminal; establishing a fourth bearer of video phone between the calling terminal and the called terminal, and performing the video phone communication between the calling terminal and the called terminal via the fourth bearer. The present invention also provides the corresponding systems, thereby realizing the Multimedia Ring Back Tone service of video phone.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of International ApplicationNo. PCT/CN2008/070478, filed on Mar. 12, 2008, which claims the benefitof Chinese Patent Application Nos. 200710073941.8, filed on Mar. 31,2007, and 200710149813.7, filed on Sep. 4, 2007, all of which are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to the fields of communications andmultimedia techniques, and more particularly, to the calling techniquesfor a video phone.

BACKGROUND

Multimedia Ring Back Tone is also referred to as personalized ring backtone service, which is a service customized by called user to provide apiece of music song or other recordings instead of the normal ring backtone for calling user. Once a customer applies for the Multimedia RingBack Tone service, a personalized ring back tone may be set as desired.When this customer is called, the personalized music song or otherrecording is played for the calling user instead of the normal ring backtone. In particular, the personalized ring back tone may be any music,song, recording, video, etc. If it is a video, the calling user terminalmust have a corresponding video media playback function to experiencethe video, which is then referred to as a Multimedia Ring Back ToneService (MRBT service) or Multimedia Caller Identification Service (MCIDservice).

The Multimedia Ring Back Tone service of video phone is one of the videophone services, which is customized by the called user to provide thecalling user a piece of dulcet and euphonic Multimedia CallerIdentification, instead of the normal ring back tone, when the calleduser is called by the calling user in a manner of video phone.

The video phone service is a point-to-point communication service thatis defined in the Universal Mobile Telecommunication System (UMTS) andmay utilize the audio and video simultaneously. It enables bidirectionalreal-time communications of both audio and video between two mobilevideo terminals, between a mobile video terminal and a stationary videoterminal, or between a mobile video terminal and a personal computer(PC).

Currently, the Multimedia Ring Back Tone service of video phone isachieved by integrating a functional module for implementing theMultimedia Ring Back Tone into the terminals, i.e., if a user downloadsand configures Multimedia Ring Back Tones, the terminal of the userplays a Multimedia Ring Back Tone for a calling terminal who calls theterminal of the user in the manner of video phone. The operators profitby charging information fee from the users who download the MultimediaRing Back Tones, without reconstruction on the network side of theoperators. In particular, the user terminal is a reconstructed videophone terminal, with a functional module of Multimedia Ring Back Tonebeing added based on the video phone terminal. When a calling requestfrom another terminal is received, the called terminal sends an alertingmessage to the calling party, and then sends a connecting message toinitiate a bearer establishment process. Meanwhile, the Multimedia RingBack Tone application of the terminal is started to prepare for playingthe Multimedia Ring Back Tone content, while a bearer of the MultimediaRing Back Tone is established between the called terminal and thecalling terminal by H.245. After the bearer establishment process isfinished, the Multimedia Ring Back Tone module of the called terminalplays the Multimedia Ring Back Tone through the established bearer,while the user of the calling terminal listens or views the content ofthe Multimedia Ring Back Tone via the bearer of video phone. Once thecalled user answers the call, the Multimedia Ring Back Tone module ofthe called terminal stops playing the content, and transfers the controlright to the user of the terminal. Then, the whole process of theMultimedia Ring Back Tone service completes.

However, as discovered by the inventor of the present invention, theprior art schemes require to reconstruct the terminals to add afunctional module for implementing the Multimedia Ring Back Tone, so asto play the content of the Multimedia Ring Back Tone during the call.Moreover, the functional module for implementing the Multimedia RingBack Tone and the functional module for the video phone calling shouldbe integrated to cooperate with each other. Therefore, the requirementfor the terminals is high. If the terminal is to select much MultimediaRing Back Tone content, the content would be stored locally. Moreover,the operators profit only by charging information fee from the users whodownload the Multimedia Ring Back Tones, which changes the prior incomemode of the operators substantially, and thus departs from therequirements of the operators.

On the other hand, due to the problem of signaling mode, the terminalmay incorrectly deem that the communication process of video phone hasalready started while the Multimedia Ring Back Tone is being played.Therefore, it is impossible for the terminals to accurately charge forthe communication duration, thereby bringing complaints from the users.

SUMMARY

Embodiments of the present invention provide calling methods and systemsfor the video phone, thereby implementing the Multimedia Ring Back Toneservice of video phone at a low cost.

An embodiment of the present invention provides a calling method for thevideo phone, including:

establishing a first bearer of video phone between a calling terminaland a Multimedia Ring Back Tone server;

playing a Multimedia Ring Back Tone to the calling terminal via thefirst bearer;

establishing a second bearer of video phone between a called terminaland the Multimedia Ring Back Tone server upon detecting that the calledterminal answers the call; and

performing a video phone communication between the calling terminal andthe called terminal via the first bearer and the second bearer.

An embodiment of the present invention provides a calling method for thevideo phone, including:

establishing a third bearer of video phone between a calling terminaland a Multimedia Ring Back Tone server;

playing a Multimedia Ring Back Tone to the calling terminal via thethird bearer; establishing a fourth bearer of video phone between thecalling terminal and a called terminal, and performing a video phonecommunication between the calling terminal and the called terminal viathe fourth bearer.

An embodiment of the present invention provides a calling system for thevideo phone, including:

a bearer establishment unit, configured to establish a first bearer ofvideo phone between a calling terminal and a Multimedia Ring Back Toneserver;

a Multimedia Ring Back Tone playback unit, configured to play aMultimedia Ring Back Tone to the calling terminal via the first bearerestablished by the bearer establishment unit;

a detection unit, configured to detect whether the called terminalanswers the call, and indicate to the bearer establishment unit that thecalled terminal has answered the call upon detecting that the calledterminal answers the call, wherein the bearer establishment unit isfurther configured to establish a second bearer of video phone betweenthe called terminal and the Multimedia Ring Back Tone server uponreceiving this indication from the detection unit; and

a communication unit, configured to perform a video phone communicationbetween the calling terminal the called terminal via the first bearerand the second bearer established by the bearer establishment unit.

An embodiment of the present invention provides another calling systemfor the video phone, including:

a bearer establishment unit, configured to establish a third bearer ofvideo phone between a calling terminal and a Multimedia Ring Back Toneserver, and establish a fourth bearer of video phone between the callingterminal and the called terminal;

a Multimedia Ring Back Tone playback unit, configured to play aMultimedia Ring Back Tone to the calling terminal via the third bearerestablished by the bearer establishment unit; and

a communication unit, configured to perform a video phone communicationbetween the calling terminal the called terminal via the fourth bearerestablished by the bearer establishment unit.

As compared with the prior art, the Multimedia Ring Back Tone serviceprovided by the embodiments of the present invention may be implementedbased on the prior network framework for the video phone. Moreover, byplaying the Multimedia Ring Back Tone to the calling terminal by theMultimedia Ring Back Tone server, it avoids the reconstruction of theprotocol layer for the terminals, thereby minimizing the effect on theterminals caused by implementing the Multimedia Ring Back Tone serviceof video phone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural diagram of a calling method for the video phonein accordance with a first embodiment of the present invention;

FIG. 2 is a flowchart of a calling method for the video phone inaccordance with a first embodiment of the present invention;

FIG. 3 is a flowchart of a calling method for the video phone inaccordance with a second embodiment of the present invention;

FIG. 4 is a flowchart of a calling method for the video phone inaccordance with a third embodiment of the present invention;

FIG. 5 is a flowchart of a calling method for the video phone inaccordance with a fourth embodiment of the present invention;

FIG. 6 is a flowchart of a calling method for the video phone inaccordance with a fifth embodiment of the present invention;

FIG. 7 is a flowchart of a calling method for the video phone inaccordance with a sixth embodiment of the present invention;

FIG. 8 is a structural diagram of a calling system for the video phonein accordance with a seventh embodiment of the present invention;

FIG. 9 is a flowchart of a calling method for the video phone inaccordance with the seventh embodiment of the present invention;

FIG. 10 is a flowchart of a calling method for the video phone inaccordance with an eighth embodiment of the present invention;

FIG. 11 is a flowchart of a calling method for the video phone inaccordance with a ninth embodiment of the present invention;

FIG. 12 is a block diagram of a calling system for the video phone inaccordance with an eleventh embodiment of the present invention; and

FIG. 13 is a block diagram of a calling system for the video phone inaccordance with a twelfth embodiment of the present invention.

DETAILED DESCRIPTION

Embodiments of the present invention are further described in detailsbelow in conjunction with the accompanying drawings for furtherclarifying the purposes, technical schemes and advantages of the presentinvention.

A first embodiment of the present invention relates to a calling methodof a video phone. In this embodiment, a Multimedia Ring Back Tone serverplays a Multimedia Ring Back Tone for the calling terminal via a firstbearer of video phone established between the calling terminal and theMultimedia Ring Back Tone server. Once it is detected that the calledterminal answers the call, a second bearer of video phone is establishedbetween the called terminal and the Multimedia Ring Back Tone server. Avideo phone communication may be performed between the calling terminaland the called terminal via the established first and second bearers.

As shown in FIG. 1, the network structure of this embodiment includes aMobile Switching Center (MSC) server, a Media Gateway (MGW), a VisitorLocation Register (VLR), a Radio Network Controller (RNC), a Node BaseStation (Node B), a Home Location Register (HLR), an AuthenticationCenter (AuC), network elements such as a Multimedia Ring Back Toneserver for providing Multimedia Ring Back Tones, as well as calling andcalled terminals. The MSC server and the VLR may be integrated togetheras a combined network element. The MSC server establishes a connectionwith the MGW by an H.248 process. The HLR and the AuC may be integratedtogether as a combined network element. (The AuC may not exist in a realnetworking situation.) As shown in FIG. 2, the specific flow includesthe following steps.

In step 201, the calling terminal or the User Equipment (UE) A sends aSETUP message to the attached MSC server A, with the ITC in the BC_IEcell carried in this message being ‘UDI’, and the Other Rate Adaptation(ORA) being ‘H.223&H.245’.

In step 202, the MSC server A issues a Send Routing Information (SRI)request to the HLR B of the called terminal or UE B, to inquire therouting information.

In step 203, the HLR B sends a Provide Roaming Number (PRN) message toan MSC server B attached to the UE B, to request the Mobile StationRoaming Number (MSRN) of the UE B.

In step 204, the MSC server B returns the MSRN of UE B to the HLR B.However, a pre-calling process is initiated before the MSRN of UE B isreturned if the MSC server B supports pre-calling.

In step 205, the HLR B returns the routing information of UE B (i.e.,the MSRN of UE B) to the MSC server A, carrying the information onwhether the called user (the user of UE B) has customized the MultimediaRing Back Tone service.

In step 206, the MSC server A initiates a Call_Proceeding process to theUE A upon obtaining the MSRN of UE B.

In step 207, the MSC server A issues an ISUP IAM message (IntegratedService Digital Network User Part Initial Address Message) to theMultimedia Ring Back Tone server. If the called user subscribes for thecalling number display service, the ISUP IAM message may carry thecalling number and the service prefix information. The Multimedia RingBack Tone server is a system for providing Multimedia Ring Back Tonesfor the video phone users, having the abilities of storing, playing andmanaging the Multimedia Ring Back Tones, and supporting the BearerIndependent Call Control (BICC)/ISDN User Part (ISUP) protocol. If thecalled user applies for the Multimedia Ring Back Tone service, theserver may provide the playback of the Multimedia Ring Back Tone for thecalling terminal, and may terminate the playback of Multimedia Ring BackTone automatically when the called user answers the call.

In step 208, the Multimedia Ring Back Tone server issues an ISUP IAMmessage to the MSC server B. If the called user subscribes for thecalling number display service, the ISUP IAM message would carry thecalling number.

In step 209, if the pre-calling process is not initiated before the MSCserver B returns the MSRN of UE B to the HLR B, the MSC server B sends acalling request message to the UE B in this step.

In step 210, the UE B returns a calling response message to the MSCserver B.

In step 211, the MSC server B sends a SETUP message to the UE B, withthe ITC in the BC_IE cell carried in the message being ‘UDI’, and theORA being ‘H.223&H.245’.

In step 212, the UE B returns a CALL CONFIRMED message without carryinga new BC_IE to the MSC server B, indicating that the video phone callingis supported. Then, the UE B starts to ring.

In step 213, the UE B returns an Alerting message to the MSC server Bafter the UE B rings.

In step 214, the MSC server B sends an Address Complete Message (ACM) tothe Multimedia Ring Back Tone server.

In step 215, the Multimedia Ring Back Tone server sends an AMC carryingMultimedia Ring Back Tone information to the MSC server A upon receivingthe ACM sent from the MSC server B.

In step 216, the MSC server A identifies the Multimedia Ring Back Toneinformation and sends an Alerting to the UE A.

In step 217, the Multimedia Ring Back Tone server sends an AnswerMessage (ANM) to the MSC server A, triggering the MSC server A to send aConnect message to the UE A. The ANM message is an ANM signal sent fromthe Multimedia Ring Back Tone server to the MSC server A, indicatingthat a communication between the Multimedia Ring Back Tone server andthe UE A may be established, and triggering the Connect message. In thisembodiment, this step is optional and may be chosen particularlydepending on the practical requirements. It should be noted that, theMSC server A may send the Connect message to the UE A upon receiving theAMC carrying Multimedia Ring Back Tone information from the MultimediaRing Back Tone server. That is, the sending of the Connect message maynot be triggered by the ANM message.

In step 218, the UE A sends a Connect ACK message to the MSC server Aupon receiving the Connect message.

In step 219, a first bearer of video phone is established between the UEA and the Multimedia Ring Back Tone server through a video phonesignaling protocol process. The video phone signaling protocol may be avideo phone signaling protocol of H.324, H.323, or Session InitiationProtocol (SIP). This embodiment is illustrated by an example ofestablishing the first bearer of video phone through the H.245 processin H.323.

In step 220, the UE A views the video Multimedia Ring Back Tone via theMultimedia Ring Back Tone server.

In step 221, the UE B sends a Connect message to the MSC server B afterthe UE B finishes the act of picking up the phone. The called partyanswering process starts.

In step 222, the MSC server B sends an ANM message to the MultimediaRing Back Tone server.

In step 223, the MSC server B sends a Connect_ACK message to the UE B.

In step 224, the Multimedia Ring Back Tone server sends an ANM messageto the MSC server A, and then the MSC server A attached to the UE Astarts to charge for the video phone communication. Since the videophone communication is charged upon detecting that the UE B answers thecall, the communication duration may be calculated and controlledaccurately in the implementing process of the Multimedia Ring Back Toneservice. Then, the MSC server A may send Connect signaling to the UE A.It should be noted that, in the practical application, the MSC server Amay not send the Connect signaling to the UE A, or the UE A may notprocess the Connect message although it is sent. In other words, it isan optional step to send the Connect message. If the UE A receives anddecides to process the Connect message, the UE A may reply with aConnect_ACK message to the MSC server A, or without replying with anymessage.

In step 225, a second bearer of video phone is established between theMultimedia Ring Back Tone server and the UE B through a multimediacommunication control signaling protocol H.245 process.

In step 226, the video phone communication of the Third Generation (3G)circuit domain is conducted between the UE A and the UE B via the firstbearer of video phone established between the UE A and the MultimediaRing Back Tone server, as well as the second bearer of video phoneestablished between the UE B and the Multimedia Ring Back Tone server.

It is apparent that in this embodiment, the Multimedia Ring Back Toneservice may be achieved based on the prior network framework for thevideo phone. Moreover, by playing the Multimedia Ring Back Tone to thecalling terminal by the Multimedia Ring Back Tone server, it avoids thereconstruction of the protocol layer for the terminals, therebyminimizing the effect on the terminals caused by implementing theMultimedia Ring Back Tone service of video phone. In addition, the UE Aand UE B each merely establish one video phone bearer with theMultimedia Ring Back Tone server, and the UE A and UE B complete thevideo phone through the Multimedia Ring Back Tone server. Further, thisembodiment places little reconstruction onto both the MSC servers andthe terminals, and thus is easy to implement.

It should be noted that, the Connect ACK messages in steps 218 and 223in this embodiment are used to acknowledge the Connect messages, and mayor may not exist depending on the practical requirements.

A second embodiment of the present invention relates to a calling methodfor a video phone, and is approximately similar to the first embodiment,except that the MSC server A notifies the UE A to establish the firstbearer of video phone by sending a Connect message to the UE A (as instep 217) in the first embodiment. While in this embodiment, instead ofsending a Connect message as shown in step 217 to the UE A after sendingthe Alerting message to the UE A (as shown in FIG. 3), the MSC server Acarries a service identifier in the Alerting message sent to the UE A.For example, a special text identifying the Multimedia Ring Back Toneservice is carried by an information element “User-User” in the Alertingmessage, so that the UE A may identify whether to receive a MultimediaRing Back Tone. The UE A starts the communication of video phoneaccording to a normal flow if the service identifier is not carried inthe Alerting message; or establishes a first bearer of video phone ifthe service identifier is carried in the Alerting message.

In addition, the MSC server A sends a Connect message to the UE A if thecalled terminal UE B answers the call and the MSC server A receives theANM message from the Multimedia Ring Back Tone server (i.e., the step224 in the first embodiment), as shown in FIG. 3.

By carrying a service identifier in the Alerting message, the normalcontinuation may not be affected if a terminal not supporting theMultimedia Ring Back Tone service receives the Alerting message, so asto be flexibly compatible with the terminals not supporting theMultimedia Ring Back Tone service. Furthermore, the UE A is required toinitiate 3 G-324M protocol interaction after receiving the Alertingmessage, and the network is required to establish a Circuit Switch Data(CSD) 64 circuit link at this time, for rapid proceeding of thesubsequent flow.

A third embodiment of the present invention relates to a calling methodfor a video phone, and is approximately similar to the first embodiment,except that in the first embodiment, the network side is not required tonotify the calling terminal (i.e., UE A) of the charging information forthe video phone communication duration, while in this embodiment, beforeit detects that the called terminal (i.e., UE B) answers the call, thenetwork side notifies the calling terminal to ignore the charging ortiming by sending a “Facility” message to the called terminal indicatingthat the network side has not charged; and upon detection that thecalled terminal answers the call, the network side notifies the callingterminal to charge or time by sending a “Facility” message to the calledterminal indicating that the network side starts to charge. Forconvenience of description, the first “Facility” message is referred toas “Facility” message FA, and the second “Facility” message is referredto as “Facility” message FB.

The specific flow is as shown in FIG. 4, wherein steps 401 to 420 arecompletely identical with steps 201 to 220, respectively, and will notbe repeated here.

In step 421, the MSC server A or the Multimedia Ring Back Tone serversends a “Facility” message FA to the UE A, informing the UE A that thisis not a normal communication and the network side has not started tocharge yet.

Steps 422 to 425 are completely identical with steps 221 to 224,respectively, and will not be repeated here.

In step 426, the MSC server A or the Multimedia Ring Back Tone serversends a “Facility” message FB to the UE A, informing the UE A that thenormal communication starts and the network side starts to charge.

Since during a normal process of video phone, the UE A establishes abearer of video phone upon receiving the Connect message in step 417,then the UE A displays “in video phone communication” to the user, andnormally, appends the duration of the video phone communication, such as“00:19”, etc. While the Multimedia Ring Back Tone service is a serviceadded based upon the video phone, if the UE is not reconstructed, thevideo phone application would deem the process the Multimedia Ring BackTone service as a process of the video phone communication, andtherefore displays “in video phone communication” and the correspondingtiming information during the playback of the Multimedia Ring Back Tone.

In order to avoid the user misunderstanding the charging information,while reducing the modification to the video phone caused by the serviceas possible so as not to affect the normal video phone communication,the UE may time according to a normal situation after receiving theConnect message in step 417, and displays information to the userindicating that the network side has not started to charge yet afterreceiving the message indicating that the network side has not startedto charge, i.e., the “Facility” message FA. For example, the displayedtiming information may be cleared, and information such as “playing ringback tone without charging” may be displayed on the screen to inform theuser that the network side has not started to charge yet. After the UEreceives a message indicating that the network side starts to charge,i.e., the “Facility” message FB, the video phone application starts totime/charge for the video phone, and displays the text such as “in videophone”, and the like.

Since the Connect message in step 417 is optional, when the UE does notreceive the Connect message distributed from the system side and thefunction of the Connect message is replaced by other signaling messages,upon receiving the signaling replacing the function of the Connectmessage, the UE displays in terms of a Multimedia Ring Back Tone, i.e.,displaying the text such as “playing ring back tone” and the like,without displaying the timing information or displaying as “00:00”. Uponreceiving the Connect message, all contents are displayed in terms of anormal video phone displaying process.

Steps 427 and 428 are completely identical with steps 225 and 226,respectively, and will not be repeated here.

It should be noted that, the Connect ACK messages in steps 418 and 424in this embodiment may or may not exist depending on the practicalrequirements. In addition, the “Facility” message FA may be sent in step421 shown in FIG. 4, or in any step after step 416 and prior to step425.

In step 425 of this embodiment, the MSC server A may or may not send theConnect message to the UE A. If the MSC server A is to send the Connectmessage, it sends the Connect message to the UE A after receiving theANM sent from the Multimedia Ring Back Tone server. The UE A may or maynot process this message.

It is apparent that the major function of the steps 421 and 426 in thisembodiment is to prompt the calling terminal whether a real the videophone has started, so that the calling terminal may accurately acquirethe communication duration calculated on the network side, so as toavoid the user of the calling terminal misunderstanding the charginginformation, solving the problem regarding when the terminal would startto charge during the Multimedia Ring Back Tone is played.

It is worth to mention that in this embodiment, the MSC server A mayfurther send information on whether the present ringing may trigger theplayback of the Multimedia Ring Back Tone to the UE A via the Alertingmessage or the Connect message distributed to the UE A in step 416 orstep 417, so that the UE A may time accurately according thereto. Forexample, if this information is not contained in the message, the UE Amay initiate the timing in a normal way, while if this information iscontained in the message, instead of initiating the timing uponreceiving the first Connect message, the UE A waits for the network tosend a subsequent message instructing to initiate the timing andinitiates the timing upon receiving this message.

The information on whether the present ringing may trigger the playbackof the Multimedia Ring Back Tone may be implemented by extending thefacility field in the message, or the User-User field in the Connectmessage. For example, if the value of the User-User field in the Connectmessage is 1, it instructs the UE A not to time upon receiving the firstConnect message; if the value of the User-User field in the Connectmessage is 0, it instructs the UE A to initiate the timing in a normalway.

It is apparent that if the information regarding whether the presentringing may trigger the playback of the Multimedia Ring Back Tone iscarried in the Alerting message or the Connect message distributed tothe UE A, it is equivalent that the step 421 is performed, and thus thesending of the “Facility” message FA may be omitted. However, the“Facility” message FB is still to be sent, which is the aforementionedmessage instructing to initiate the timing.

A fourth embodiment of the present invention relates to a calling methodfor a video phone, and is approximately similar to the first embodiment,except that in the first embodiment, the network side may not notify thecalling terminal (i.e., UE A) of the charging information for therelated video phone communication duration, while in this embodiment,before it detects that the called terminal (i.e., UE B) answers thecall, the network side notifies the calling terminal to ignore thecharging or timing by sending a Short Message Service (SMS) message tothe called terminal indicating that the network side has not charged;and upon detecting that the called terminal answers the call, thenetwork side notifies the calling terminal to charge or time by sendingan SMS message to the called terminal indicating that the network sidestarts charging. For convenience of description, the first SMS messageis referred to as SMS message SA, and the second SMS message is referredto as SMS message SB.

The specific flow is as shown in FIG. 5, wherein steps 501 to 520 arecompletely identical with steps 201 to 220, respectively, and will notbe repeated here.

In step 521, the MSC server A sends an SMS message SA to the UE A,informing the UE A that this is not a normal communication and thenetwork side has not started to charge yet. The UE A may display theinformation indicating that the network side has not started to chargeyet to the user upon receiving the SMS message SA. For example, theinformation such as “playing ring back tone without charging” may bedisplayed on the screen to inform the user that the network side has notstarted to charge.

Steps 522 to 525 are completely identical with steps 221 to 224,respectively, and will not be repeated here.

In step 526, the MSC server A sends an SMS message SB to the UE A,informing the UE A that the normal communication starts and the networkside starts to charge.

The sending of the SMS messages in steps 521 and 526 is essentially alogic process. In the practical implementation, the SMS may be sent bythe MSC server A, or by the MSC server A in cooperation with a supportdevice such as a short message gateway or the like. In this embodiment,the MSC server A sending the SMS means that the SMS message is triggeredby some device and is sent via the MSC server A.

Steps 527 and 528 are completely identical with steps 225 and 226,respectively, and will not be repeated here.

It should be noted that, the Connect ACK messages in steps 518 and 524in this embodiment may or may not exist depending on the practicalrequirements. In addition, the SMS message A may be sent in step 521shown in FIG. 5, or in any step after step 516 and prior to step 525.

In step 525 of this embodiment, the MSC server A may or may not send theConnect message to the UE A. If the MSC server A is to send the Connectmessage, it sends the Connect message to the UE A after receiving theANM sent from the Multimedia Ring Back Tone server. The UE A may or maynot process this message.

It is apparent that the major function of the steps 521 and 526 in thisembodiment is to prompt the calling terminal whether a real the videophone has started, so that the calling terminal may accurately acquirethe communication duration calculated on the network side, so as toavoid the user of the calling terminal misunderstanding the charginginformation, thereby solving the problem regarding when the terminalwould start to charge during the Multimedia Ring Back Tone is played.Since the SMS is a common communication manner for terminals, theinformation indicating whether the network side has started to chargemay be represented by the content carried by the SMS. The correspondinginformation may be represented by carrying what content in the SMS maybe defined in advance. For example, it may indicate that the video phonehas not started yet and that it is the Multimedia Ring Back Tone servicecurrently by utilizing the “MRBT Begin” carried by the SMS message. Thecalling terminal may consider the current session as a Multimedia RingBack Tone session after receiving the SMS message, instead of processingthe current session as a video phone communication. It may utilize the“VP Begin” carried by the SMS message as a flag for the video phone tostart. The calling terminal may consider the current session as a videophone communication after receiving this SMS message, and process thecurrent session as a normal video phone communication. Since the SMSmessage may carry different content and information, the informationrepresented by the SMS message may be different, depending on thedefinition made in advance.

In addition, it is worth to mention that in this embodiment, it isillustrated by the example that the calling terminal is informed ofwhether the network side has started to charge by an SMS message, whilein the practical applications, the calling terminal may be informed byother means, such as the Multimedia Message Services (MMS), theElectronic mail (E-mail), the Instant Messenger (IM), the Push Message,etc. The specific implementing manner is similar to that of thisembodiment, and will not be repeated here.

It should be noted that in this embodiment, the MSC server A may furthersend information regarding whether the present ringing may trigger theplayback of the Multimedia Ring Back Tone to the UE A via the Alertingmessage or the Connect message distributed to the UE A in step 516 orstep 517, so that the UE A may time accurately according thereto. Forexample, if this information is not contained in the message, the UE Amay initiate the timing in a normal manner, while if this information iscontained in the message, instead of initiating the timing uponreceiving the first Connect message, the UE A waits for the network tosend a subsequent message instructing to initiate the timing andinitiates the timing upon receiving this message.

The information regarding whether the present ringing may trigger theplayback of the Multimedia Ring Back Tone may be implemented byextending the facility field in the message, or the User-User field inthe Connect message. For example, if the value of the User-User field inthe Connect message is 1, it instructs the UE A not to time uponreceiving the first Connect message; if the value of the User-User fieldin the Connect message is 0, it instructs the UE A to initiate thetiming in a normal way.

It is apparent that if the information regarding whether the presentringing may trigger the playback of the Multimedia Ring Back Tone iscarried in the Alerting message or the Connect message distributed tothe UE A, it is equivalent that the step 521 is performed, and thesending of the SMS message A may be omitted. However, the SMS message SBis still to be sent, which is the aforementioned message instructing toinitiate the timing.

A fifth embodiment of the present invention relates to a calling methodfor a video phone, and is approximately similar to the first embodiment,except that in the first embodiment, the network side may not notify thecalling terminal (i.e., UE A) of the charging information for therelated video phone communication duration, while in this embodiment,before it detects that the called terminal (i.e., UE B) answers thecall, the network side notifies the calling terminal to ignore thecharging or timing by sending a Command or Indication message of H.245to the called terminal indicating that the network side has not startedto charge; and upon detecting that the called terminal answers the call,the network side notifies the calling terminal to charge or time bysending a Command or Indication message of H.245 to the called terminalindicating that the network side starts to charge. For convenience ofdescription, the first Command or Indication message of H.245 isreferred to as Command or Indication message A of H.245 and the secondCommand or Indication message of H.245 is referred to as Command orIndication message HB of H.245 hereinafter.

The specific flow is as shown in FIG. 6, wherein steps 601 to 620 arecompletely identical with steps 201 to 220, respectively, and will notbe repeated here.

In step 621, the Multimedia Ring Back Tone server sends a Command orIndication message A of H.245 to the UE A, informing the UE A that thisis not a normal communication and the network side has not started tocharge yet. The UE A may display the information indicating that thenetwork side has not started to charge yet to the user upon receivingthe Command or Indication message HA of H.245. For example, theinformation such as “playing ring back tone without charging” may bedisplayed on the screen to inform the user that the network side has notstarted to charge yet.

Steps 622 to 625 are completely identical with steps 221 to 224,respectively, and will not be repeated here.

In step 626, the Multimedia Ring Back Tone server sends a Command orIndication message HB of H.245 to the UE A, informing the UE A that anormal communication starts and the network side starts to charge.

Steps 627 and 628 are completely identical with steps 225 and 226,respectively, and will not be repeated here.

It should be noted that, the Connect ACK messages in steps 618 and 624in this embodiment may or may not exist depending on the practicalrequirements. In addition, the Command or Indication message HA of H.245may be sent in step 621 shown in FIG. 6, or in any step after step 619and prior to step 625.

In step 625 of this embodiment, the MSC server A may or may not send theConnect message to the UE A. If the MSC server A is to send the Connectmessage, it sends the Connect message to the UE A after receiving theANM sent from the Multimedia Ring Back Tone server. The UE A may or maynot process this message.

It is apparent that the major function of the steps 621 and 626 in thisembodiment is to prompt the calling terminal whether a real the videophone has started, so that the calling terminal may accurately acquirethe communication duration calculated on the network side, so as toavoid the user of the calling terminal misunderstanding the charginginformation, thereby solving the problem regarding when the terminalwould start to charge during the Multimedia Ring Back Tone is played.Since the whole developing process of Multimedia Ring Back Tone requiresthe support of H.245, the information indicating whether the networkside has started to charge may be represented by the Command orIndication messages of H.245. The corresponding information may berepresented by what Command or Indication message of H.245 is defined inadvance, for example, if the Indication message of USER INPUT in H.245employs the format of

Indication Message : user input UserInputIndication ::=CHOICE {nonStandard NonStandardParameter, alphanumeric GeneralString, ... }then it may indicate that the video phone has not started yet and thatit is the Multimedia Ring Back Tone service currently by carrying 10000with the “GeneralString” field in the Indication message of USER INPUT.Upon receiving this message, the calling terminal may consider thecurrent session as a Multimedia Ring Back Tone session, instead ofprocessing the current session as a video phone call. On the other hand,it may indicate that Multimedia Ring Back Tone service ends and that thevideo phone starts by carrying 10001 with the “GeneralString” field inthe Indication message of USER INPUT. Upon receiving this message, thecalling terminal may consider the current session as a video phonecommunication, and process the current session as a normal video phonecommunication. Since the Indication message of USER INPUT may carry avariety of data, the foregoing scheme is only a possible way and values.

Take the H.245 Command message as an example, the H.245 Command messageA may further transmit a Dual-tone multi-frequency (DTMF) a signal by aUSER INPUT Indication (UII), indicating the UE A to stop the timing ofthe terminal. Upon receiving this message, the UE A stops timing, clearsthe timer, and prompts the user that a Multimedia Ring Back Tone is tobe played. An H.245 Command message b may instruct the UE A to starttiming by transmitting a DTMF B signal. Upon receiving this message, theUE A starts timing, and prompts the user to start the normalcommunication.

Other commands and indications of H.245 or other messages may beemployed in a specific implementing process. The specific implementingmanner is similar to that of the present embodiment, and will not berepeated here.

It should be noted that in this embodiment, the MSC server A may furthersend information on whether the present ringing may trigger the playbackof the Multimedia Ring Back Tone to the UE A via the Alerting message orthe Connect message distributed to the UE A in step 616 or step 617, sothat the UE A may time accurately according thereto. For example, ifthis information is not contained in the message, the UE A initiates thetiming in a normal manner, while if this information is contained in themessage, instead of initiating the timing upon receiving the firstConnect message, the UE A waits for the network to send a subsequentmessage instructing to initiate the timing and initiates the timing uponreceiving this message.

The information on whether the present ringing may trigger the playbackof the Multimedia Ring Back Tone may be implemented by extending thefacility field in the message, or the User-User field in the Connectmessage. For example, if the value of the User-User field in the Connectmessage is 1, it instructs the UE A not to time upon receiving the firstConnect message; if the value of the User-User field in the Connectmessage is 0, it instructs the UE A to initiate the timing in a normalway.

It is apparent that if the information regarding whether the presentringing may trigger the playback of the Multimedia Ring Back Tone iscarried in the Alerting message or the Connect message distributed tothe UE A, it is equivalent that the step 621 is performed, and thesending of the Command or Indication message HA of H.245 may be omitted.However, the Command or Indication message HB of H.245 is still to besent, which is the aforementioned message instructing to initiate thetiming.

A sixth embodiment of the present invention relates to a calling methodfor a video phone, and is approximately similar to the first embodiment,except that in the first embodiment, the network side is may not notifythe calling terminal (i.e., UE A) of the charging information for therelated video phone communication duration, while in this embodiment,before it detects that the called terminal (i.e., UE B) answers thecall, the network side notifies the calling terminal to ignore thecharging or timing by sending a Unstructured Supplementary Service Data(USSD) signal to the called terminal indicating that the network sidehas not started to charge yet; and upon detecting that the calledterminal answers the call, the network side notifies the callingterminal to charge or time by sending a USSD signal to the calledterminal indicating that the network side starts charging. Forconvenience of description, the first USSD signal is referred to as USSDsignal A, and the second USSD signal is referred to as USSD signal B.

The specific flow is as shown in FIG. 7, wherein steps 701 to 720 arecompletely identical with steps 201 to 220, respectively, and will notbe repeated here.

In step 721, the MSC server A sends a USSD signal A to the UE A,informing the UE A that this is not a normal communication and thenetwork side has not started to charge yet. The UE A may display theinformation indicating that the network side has not started to chargeyet to the user upon receiving the USSD signal A. For example, theinformation such as “playing ring back tone without charging” may bedisplayed on the screen to inform the user that the network side has notstarted to charge yet.

Steps 722 to 725 are completely identical with steps 221 to 224,respectively, and will not be repeated here.

In step 726, the MSC server A sends a USSD signal B to the UE A,informing the UE A that the normal call starts and that the network sidestarts to charge.

Steps 727 and 728 are completely identical with steps 225 and 226,respectively, and will not be repeated here.

It should be noted that, the Connect ACK messages in steps 718 and 724in this embodiment may or may not exist depending on the practicalrequirements. In addition, the USSD signal A may be sent in step 721shown in FIG. 7, or in any step after step 716 and prior to step 725.

In step 725 of this embodiment, the MSC server A may or may not send theConnect message to the UE A. If the MSC server A is to send the Connectmessage, it sends the Connect message to the UE A after receiving theANM sent from the Multimedia Ring Back Tone server. The UE A may or maynot process this message.

It is apparent that the major function of the steps 721 and 726 in thisembodiment is to prompt the calling terminal whether a real the videophone has started, so that the calling terminal may accurately acquirethe communication duration calculated on the network side, so as toavoid the user of the calling terminal misunderstanding the charginginformation, thereby solving the problem regarding when the terminalwould start to charge during the Multimedia Ring Back Tone is played.Since the USSD is a common communication manner for terminals, theinformation indicating whether the network side has started to chargemay be carried by the USSD signal. The corresponding information may berepresented by carrying what USSD signal is defined in advance. Forexample, it may indicate to the calling terminal that it is theMultimedia Ring Back Tone service currently by a flag indicating thatthe Multimedia Ring Back Tone starts carried in the USSD signal. Uponreceiving this USSD signal, the calling terminal may consider thecurrent session as a Multimedia Ring Back Tone session, instead ofprocessing the current session as a video phone communication. On theother hand, it may indicate to the calling terminal that the video phonestarts by a flag, carried in the USSD signal, indicating that the videophone starts. Upon receiving this USSD signal, the calling terminal mayconsider the current session as a video phone communication, and processthe current session as a normal video phone communication. DifferentUSSD signals may represent different information, depending on thedefinition in advance.

In addition, it is worth to mention that in this embodiment, it isillustrated by the example that the calling terminal is informed ofwhether the network side has started to charge by a USSD signal. In thepractical applications, the calling terminal may be informed by othermeans, such as the Session Initiation Protocol (SIP), the Hyper TextTransfer Protocol (HTTP), the Real-time Streaming Protocol (RTSP)signaling, etc. The specific implementing manner is similar to that ofthe present embodiment except the underlying link, and will not berepeated here.

It should be noted that in this embodiment, the MSC server A may furthersend information regarding whether the present ringing may trigger theplayback of the Multimedia Ring Back Tone to the UE A via the Alertingmessage or the Connect message distributed to the UE A in step 716 orstep 717, so that the UE A may time accurately according thereto. Forexample, if this information is not contained in the message, the UE Amay initiate the timing in a normal manner, while if this information iscontained in the message, instead of initiating the timing uponreceiving the first Connect message, the UE A waits for the network tosend a subsequent message instructing to initiate the timing andinitiates the timing upon receiving this message.

The information regarding whether the present ringing may trigger theplayback of the Multimedia Ring Back Tone may be implemented byextending the facility field in the message, or implemented by extendingthe User-User field in the Connect message. For example, if the value ofthe User-User field in the Connect message is 1, it instructs the UE Anot to time upon receiving the first Connect message; if the value ofthe User-User field in the Connect message is 0, it instructs the UE Ato initiate the timing in a normal way.

It is apparent that if the information regarding whether the presentringing may trigger the playback of the Multimedia Ring Back Tone iscarried in the Alerting message or the Connect message distributed tothe UE A, it is equivalent that the step 721 is performed, and thesending of the USSD signal A may be omitted. However, the USSD signal Bis still to be sent, which is the forgoing message instructing toinitiate the timing.

A seventh embodiment of the present invention relates to a callingmethod for a video phone. In this embodiment, a Multimedia Ring BackTone server plays a Multimedia Ring Back Tone for the calling terminalvia a third bearer of video phone established between the callingterminal and the Multimedia Ring Back Tone server. A fourth bearer ofvideo phone is established between the calling terminal and the calledterminal, and the video phone communication is performed between thecalling terminal and the called terminal via the fourth bearer. Thethird and fourth bearers are video phone communication links establishedby the video phone protocol of H.324, H.323, or SIP, wherein the presentembodiment is illustrated by an example of establishing the third andfourth bearers with an H.245 process in H.323.

The network structure of this embodiment is shown in FIG. 8, withdifferent Multimedia Ring Back Tone servers being established indifferent regions, wherein the MSC server and the VLR are stillintegrated together as a combined network element, the MSC server stillestablishes a connection with the MGW by an H.248 process, and the HLRand the AuC are still integrated together as a combined network element.The specific flow is shown in FIG. 9.

Step 901, the calling terminal or UE A sends a SETUP message to theattached MSC server A, with the ITC in the BC_IE cell carried in themessage being ‘UDI’, and the ORA being ‘H.223&H.245’.

In step 902, the MSC server A issues an SRI request to the HLR B of thecalled terminal, i.e., UE B.

In step 903, the HLR B acquires the Mobile Station Roaming Number (MSRN)of the UE B from the MSC server B attached to the UE B.

In step 904, the MSC server B returns the MSRN of UE B to the HLR B.However, a pre-calling process is initiated before the MSRN of UE B isreturned if the MSC server B supports pre-calling.

In step 905, the HLR B returns the routing information of UE B (i.e.,the MSRN of UE B) to the MSC server A, carrying the information onwhether the called user (the user of UE B) has customized the MultimediaRing Back Tone service.

In step 906, the MSC server A initiates a Call_Proceeding process to theUE A after obtaining the MSRN of UE B.

In step 907, the MSC server A issues an ISUP IAM message to the MSCserver B. If the called user subscribes for the calling number displayservice, the ISUP IAM message would carry the calling number.

In step 908, if the pre-calling process is not initiated before the MSCserver B returns the MSRN of UE B to the HLR B, the MSC server B sends acalling request message to the UE B in this step.

In step 909, the UE B returns a calling response message to the MSCserver B.

In step 910, the MSC server B sends a SETUP message to the UE B, withthe ITC in the BC_IE cell carried in the message being ‘UDI’, and theORA being ‘H.223&H.245’.

In step 911, the UE B returns a CALL CONFIRMED message without carryinga new BC_IE to the MSC server B, indicating that the video phone callingis supported.

In step 912, the UE B returns an Alerting message to the MSC server Bafter the UE B rings.

In step 913, the MSC server B returns a BICC ACM message to the MSCserver A.

In step 914, the MSC server A returns an Alerting message to the MSCserver B.

In step 915, the MSC server A issues a BICC IAM message to theMultimedia Ring Back Tone server, carrying the information on whetherthe UE B has customized Multimedia Ring Back Tone service.

In step 916, the Multimedia Ring Back Tone server returns a BICC ACMmessage to the MSC server A. The MSC server A identifies the ACM messagesent from the Multimedia Ring Back Tone server, and does not send anAlerting message to the calling terminal.

In step 917, the Multimedia Ring Back Tone server sends a BICC ANMmessage to the MSC server A. After receiving the BICC ANM message, theMSC server A sends connecting signaling CONNECT to the calling terminalUE A, while listening whether a message is returned from the MSC serverB. This ANM message represents that a communication between theMultimedia Ring Back Tone server and the UE A may be established, and isused to trigger the Connect message. In this embodiment, this step is anoptional step and may be chosen particularly depending on the practicalrequirements.

In step 918, the UE A sends a Connect ACK message to the MSC server Aupon receiving the Connect message.

In step 919, the UE A and the Multimedia Ring Back Tone server establisha third bearer of video phone through a multimedia communication controlsignaling protocol H.245 process. After the establishment of the thirdbearer of video phone is completed, the Multimedia Ring Back Toneinformation played by the Multimedia Ring Back Tone server may beviewed.

In step 920, the called terminal UE B sends a response message CONNECTto the MSC server B.

In step 921, the MSC server B returns a BICC ANM message to the MSCserver A.

In Step 922, the MSC server B returns a Connect ACK message to the UE B.

In step 923, the MSC server A sends a BICC Release message to theMultimedia Ring Back Tone server, instructing to remove the third bearerestablished between the Multimedia Ring Back Tone server and the UE A.

In step 924, the third bearer of video phone established between theMultimedia Ring Back Tone server and the UE A is removed.

In step 925, the Multimedia Ring Back Tone server returns a BICC ReleaseComplete message to the MSC server A.

In step 926, the UE A and the UE B establish a fourth bearer of videophone through a multimedia communication control signaling protocolH.245 process.

In step 927, the video phone communication in the 3G circuit domain isperformed between the UE A and UE B via the fourth bearer of video phoneestablished between the UE A and UE B.

In step 928, after the video phone call finishes, the fourth bearer andthe underlying circuits established between the UE A and UE B areremoved.

It is apparent that in this embodiment, the Multimedia Ring Back Toneservice may be achieved based on the prior network framework for a videophone. Moreover, by playing the Multimedia Ring Back Tone to the callingterminal by the Multimedia Ring Back Tone server, it avoids thereconstruction of the protocol layer for the terminals, therebyminimizing the effect on the terminals caused by implementing theMultimedia Ring Back Tone service of video phone.

Furthermore, before establishing the fourth bearer of video phone, thethird bearer established between the calling terminal and the MultimediaRing Back Tone server is to be removed upon detecting that the calledterminal answers the call, so that the circuits occupied by theMultimedia Ring Back Tone server may be released immediately when theuser communication is connected, thereby saving the limited circuitresources.

It is worth to mention that in this embodiment, after the establishmentof the fourth bearer between the calling terminal and the calledterminal is completed, the network side charges for the video phonecommunication, so that the communication duration may be calculated andcontrolled accurately in the implementing process of the Multimedia RingBack Tone service.

It should be noted that in this embodiment, the MSC server A may furthersend information regarding whether the present ringing may trigger theplayback of the Multimedia Ring Back Tone to the UE A via the Alertingmessage or the Connect message distributed to the UE A in step 914 orstep 917, so that the UE A may time accurately according thereto. Forexample, if this information is not contained in the message, the UE Amay initiate the timing in a normal manner, while if this information iscontained in the message, instead of initiating the timing uponreceiving the first Connect message, the UE A waits for the network tosend a subsequent message instructing to initiate the timing andinitiates the timing upon receiving this message.

The information on whether the present ringing may trigger the playbackof the Multimedia Ring Back Tone may be implemented by extending thefacility field in the message, or the User-User field in the Connectmessage. For example, if the value of the User-User field in the Connectmessage is 1, it instructs the UE A not to time upon receiving the firstConnect message; if the value of the User-User field in the Connectmessage is 0, it instructs the UE A to initiate the timing in a normalway.

An eighth embodiment of the present invention relates to a callingmethod for a video phone, and is approximately similar to the seventhembodiment except that in the seventh embodiment, the third and forthbearers are video phone communication links established through thevideo phone protocol of H.324, H.323, or SIP, while in this embodiment,the third and forth bearers are CSD links, and the logic channels ofvideo phone are established on the CSD links through the video phoneprotocol of H.324, H.323, or SIP. The third bearer may be decomposedinto: a fifth bearer from the calling terminal to the MSC server of thecalling terminal, and a sixth bearer from the MSC server of the callingterminal to the Multimedia Ring Back Tone server; the fourth bearer maybe decomposed into: the fifth bearer from the calling terminal to theMSC server of the calling terminal, and a seventh bearer from the MSCserver of the calling terminal to the called terminal.

The specific flow is as shown in FIG. 10, wherein steps 1001 to 1018 arecompletely identical with steps 901 to 918, respectively, and will notbe repeated here.

In step 1019, the fifth bearer is established between the UE A and theMSC server A, and the sixth bearer is established between the MSC serverA and the Multimedia Ring Back Tone server. Both the fifth and sixthbearers are CSD links. Then, an H.245 process is established based onthe fifth and sixth bearers. After the establishment, the user of thecalling terminal may view the Multimedia Ring Back Tone played by theMultimedia Ring Back Tone server.

Steps 1020 to 1024 are completely identical with steps 920 to 924,respectively, and will not be repeated here.

In step 1025, the Multimedia Ring Back Tone server returns a BICCRelease Complete message to the MSC server A. The MSC server A sends aFacility message to the UE A, indicating that the bearer between the MSCserver A and the Multimedia Ring Back Tone server (i.e., the sixthbearer) has been removed, and that a CS64 kbps bearer link between theMSC server A and the MSC server B has been established. Apparently, itis merely a specific implementing manner to carry this information bythe facility message, and other message may be used instead in practice.The major purpose of this step is to prompt the calling terminal or theUE A that the establishment of two H.245 bearer processes may beinvolved during the whole calling process of video phone, and instructsthe UE A to prepare for the second H.245 bearer process upon receivingthe facility message, i.e., preparing for the establishment of a bearerwith the UE B based on the existing CS64 kbp link.

This step may be at the location shown in FIG. 10, or at any locationbetween the steps 1023 and 1026, with the major function being to promptthe establishment of the two H.245 bearer processes.

In step 1026, an H.245 process is established based on the existingfifth bearer between the UE A and the MSC server A, as well as theseventh bearer between the MSC server A and the UE B. i.e., establishingthe fourth bearer between the calling terminal UE A and the calledterminal UE B.

Steps 1027 and 1028 are completely identical with steps 927 and 928,respectively, and will not be repeated here.

It is apparent that as compared with the seventh embodiment, the presentembodiment may provide a faster establishing process of the two H.245bearer processes, with little modification and no implementing barrier.

A ninth embodiment of the present invention relates to a calling methodfor a video phone. Based on the seventh embodiment, this embodimentachieves the purpose of removing the third bearer of video phone betweenthe UE A and the Multimedia Ring Back Tone server by initiating H.245self-hangup processes respectively by the UE A and the Multimedia RingBack Tone server. The specific flow is shown in FIG. 11.

Steps 1101 to 1120 are completely identical with steps 901 to 920,respectively, and will not be repeated here.

In step 1121, the MSC server B returns a BICC ANM message to the MSCserver A. Moreover, the MSC server A sends a facility message to UE A.After receiving the facility message, the UE A initiates an H.245self-hangup process (without sending the hangup signaling “End Session”to the other party of the communication), and releases the localresources directly.

Step 1122 is completely identical with the step 923.

In step 1123, the MSC server A sends a BICC Release message to theMultimedia Ring Back Tone server, which initiates an H.245 self-hangupprocess (without sending the hangup signaling “End Session” to the otherparty of the communication) upon receiving this message.

In step 1124, after the H.245 self-hangup process is completed, the UE Ainitiates the establishment of a second H.245 bearer, i.e., initiatingthe establishment process of the fourth bearer of video phone betweenthe UE A and UE B as described in the seventh embodiment.

In step 1125, the Multimedia Ring Back Tone server returns a BICCRelease Complete message to the MSC server A.

Steps 1126 and 1127 are completely identical with steps 927 and 928,respectively, and will not be repeated here.

It is apparent that, this embodiment differs from the seventh embodimentin that the network side distributes a prompt message (i.e., thefacility message above) to the calling terminal, indicating the callingterminal that the playback process of the Multimedia Ring Back Toneservice ends, and requiring the calling terminal to establish the secondH.245 bearer. The calling terminal may initiate a self-hangup processupon receiving this prompt message. In this way, the first H.245 bearerestablished with the Multimedia Ring Back Tone server ends in terms ofhanging up the communication link by the calling terminal. Such processis coincident with the normal communication flow, and further reducesthe whole duration of network continuation, thereby reducing the timespent in switching between services, and improving the experience of theusers.

The whole Multimedia Ring Back Tone service may be viewed as twocommunications, with the first communication being the Multimedia RingBack Tone service and the second being the normal communication of videophone. The calling terminal ends the session of the whole MultimediaRing Back Tone by self-hanging up according to the prompt messagedistributed from the network side, and initiates an establishmentprocess of a new H.245 bearer for the video phone communication afterself-hanging up the session, so as to achieve the normal video phonecommunication successfully.

In step 1123, the Multimedia Ring Back Tone server initiates aself-hangup process upon receiving the BICC Release Complete messagefrom the MSC server A. The Multimedia Ring Back Tone server may serve asa logic terminal during the whole Multimedia Ring Back Tone service, forproviding the content of the Multimedia Ring Back Tone. After theprocess of providing the content of the Multimedia Ring Back Tone ends,the Multimedia Ring Back Tone server may participate in the wholeprocess of removing the Multimedia Ring Back Tone bearer as a party ofthe session.

The self-hangup process initiated by the UE A accomplishes thesubstantially similar function as the self-hangup process initiated bythe Multimedia Ring Back Tone server (i.e., removing the bearer betweenthe UE A and the Multimedia Ring Back Tone server). Therefore, theself-hangup process may be initiated in the UE A only, or in theMultimedia Ring Back Tone server only. However, for consideration of thecooperation of the whole system and to reduce the possibility of systemerror as possible, self-hangup processes may be initiated in the UE Aand in the Multimedia Ring Back Tone server respectively. Moreover, thetwo self-hangup processes have no strict order in practicalapplications. Further, in step 1123 of the present embodiment, the MSCserver A sending the BICC Release message to the Multimedia Ring BackTone server is essentially used to instruct the Multimedia Ring BackTone server to perform the self-hangup process. Accordingly, step 1123may be omitted if the Multimedia Ring Back Tone server does not performthe self-hangup process.

It is apparent that in the first to sixth embodiments of the presentinvention, after the whole Multimedia Ring Back Tone service finishes,the Multimedia Ring Back Tone server still resides in the subsequentcommunication process of video phone, serving as a back-to-back server.For convenience of description, this scheme is referred to as a bridgingscheme. In the seventh to ninth embodiments of the present invention,after the whole Multimedia Ring Back Tone service finishes, thecommunication link between the Multimedia Ring Back Tone server and thecalling terminal is removed, and a communication link for the videophone is to be established between the calling terminal and the calledterminal. The most significant feature in this scheme is that thecalling terminal establishes H.245 bearers with the Multimedia Ring BackTone server and the called terminal respectively. For convenience ofdescription, this scheme is referred to as a non-bridging scheme.

A tenth embodiment of the present invention relates to a calling methodfor a video phone, and is a combination of the bridging scheme in thefirst to sixth embodiments of the present invention and the non-bridgingscheme in the seventh to ninth embodiments of the present invention.

In particular, the calling terminal carries the type of Multimedia RingBack Tone schemes supported by this terminal (i.e., supporting thebridging scheme or the non-bridging scheme) in the SETUP message sent tothe MSC server A. For example, whether the terminal supports thebridging scheme or the non-bridging scheme may be indicated by the valueof the User-User field in the SETUP message. It may be defined inadvance that, the User-User field being 0 represents that the terminalsupports the bridging scheme and the User-User field being 1 representsthat the terminal supports the non-bridging scheme.

If the network side recognizes that the calling terminal supports thebridging scheme, the subsequent flow may be identical with either one ofthe first to sixth embodiments above; if the network side recognizesthat the calling terminal supports the non-bridging scheme, thesubsequent flow may be identical with either one of the seventh to ninthembodiments above, which will not be repeated here.

An eleventh embodiment of the present invention relates to a callingsystem for a video phone, as shown in FIG. 12, including: a bearerestablishment unit, for establishing a first bearer of video phonebetween a calling terminal and a Multimedia Ring Back Tone server; aMultimedia Ring Back Tone playback unit, for playing the Multimedia RingBack Tone to the calling terminal via the first bearer established bythe bearer establishment unit; a detection unit, for detecting whetherthe called terminal answers the call, and indicating the bearerestablishment unit that the called terminal has answered the call upondetecting that the called terminal answers the call, wherein the bearerestablishment unit is further configured to establish a second bearer ofvideo phone between the called terminal and the Multimedia Ring BackTone server upon receiving this indication from the detection unit; acommunication unit, for performing a video phone communication betweenthe calling terminal and the called terminal via the first bearer andthe second bearer established by the bearer establishment unit. In thisway, the Multimedia Ring Back Tone service may be achieved based on theprior network framework for the video phone. Moreover, by playing theMultimedia Ring Back Tone to the calling terminal by the Multimedia RingBack Tone playback unit, it avoids the reconstruction of the protocollayer for the terminals, thereby minimizing the effect on the terminalscaused by implementing the Multimedia Ring Back Tone service of videophone.

The Multimedia Ring Back Tone playback unit is within the MultimediaRing Back Tone server, and the bearer establishment unit establishes thefirst and second bearers through the video phone signaling protocolprocesses. The video phone signaling protocol may be a video phonesignaling protocol of H.324, H.323, or SIP.

It is worth to mention that the calling system for the video phone inthis embodiment may further include a charging unit for charging for thevideo phone communication, wherein the detection unit is furtherconfigured to indicate to the charging unit that the called terminal hasanswered the call upon detecting that the called terminal answers thecall, and the charging unit starts to charging for the video phonecommunication upon receiving this indication. Therefore, thecommunication duration may be calculated and controlled accurately inthe implementing process of the Multimedia Ring Back Tone service.

The calling system for the video phone in this embodiment may furtherinclude a notify unit for notifying the calling terminal to ignore thecharging or timing, and for notifying the calling terminal to startcharging or timing. The detection unit is further configured to indicateto the notify unit that the called terminal has answered the call upondetecting that the called terminal answers the call. The notify unitnotifies the calling terminal to ignore the charging or timing beforereceiving this indication from the detection unit, and notifies thecalling terminal to start charging or timing up receiving thisindication from the detection unit. Therefore, the calling terminal mayaccurately acquire the communication duration calculated on the networkside, so as to avoid the user of the calling terminal misunderstandingthe charging information.

A twelfth embodiment of the present invention relates to a callingsystem for a video phone, as shown in FIG. 13, including: a bearerestablishment unit, for establishing a third bearer of video phonebetween a calling terminal and a Multimedia Ring Back Tone server, andestablishing a fourth bearer of video phone between the calling terminaland the called terminal; a Multimedia Ring Back Tone playback unit, forplaying the Multimedia Ring Back Tone to the calling terminal via thethird bearer established by the bearer establishment unit; acommunication unit, for performing a video phone communication betweenthe calling terminal the called terminal via the fourth bearerestablished by the bearer establishment unit. In this way, theMultimedia Ring Back Tone service may be achieved based on the priornetwork framework for the video phone.

The calling system for the video phone in this embodiment may furtherinclude a detection unit for detecting whether the called terminalanswers the call, and a bearer removal unit for removing the bearers.

If the third and fourth bearers are Circuit Switch Data (CSD) links, andthe third bearer may be decomposed into a fifth bearer from the callingterminal to the MSC server of the calling terminal and a sixth bearerfrom the MSC server of the calling terminal to the Multimedia Ring BackTone server while the fourth bearer may be decomposed into the fifthbearer and a seventh bearer from the MSC server of the calling terminalto the called terminal, then upon detecting that the called terminalanswers the call, the detection unit indicates to the bearer removalunit that the called terminal has answered the call, wherein the bearerremoval unit removes the sixth bearer from the MSC server of the callingterminal to the Multimedia Ring Back Tone server after receiving thisindication.

If the third and fourth bearers are video phone communication linksestablished through a video phone protocol of H.324, H.323, or SIP, thenupon detecting that the called terminal answers the call, the detectionunit indicates to the bearer removal unit that the called terminal hasanswered the call, wherein the bearer removal unit removes the thirdbearer established by the bearer establishment unit after receiving thisindication, and instructs the bearer establishment unit to establish thefourth bearer.

As can be seen, the circuits occupied by the Multimedia Ring Back Toneserver may be released immediately when the user communication isconnected (i.e., the detection unit detects that the called terminalanswers the call), thereby effectively saving the limited circuitresources.

As described above, in the embodiments of the present invention, theMultimedia Ring Back Tone server plays a Multimedia Ring Back Tone forthe calling terminal by the first bearer of video phone establishedbetween the calling terminal and the Multimedia Ring Back Tone server.Upon detecting that the called terminal answers the call, a secondbearer of video phone is established between the calling terminal andthe Multimedia Ring Back Tone server. The video phone communications maybe performed between the calling terminal and the called terminal viathe first bearer and the second bearer established. Or, the MultimediaRing Back Tone server plays a Multimedia Ring Back Tone for the callingterminal by a third bearer of video phone established between thecalling terminal and the Multimedia Ring Back Tone server. A fourthbearer of video phone is established between the calling terminal andthe called terminal, and the video phone communication is performedbetween the calling terminal and the called terminal via the fourthbearer. In this way, the Multimedia Ring Back Tone service may beachieved based on the prior network framework for the video phone.Moreover, by playing the Multimedia Ring Back Tone to the callingterminal by the Multimedia Ring Back Tone server, it avoids thereconstruction of the protocol layer for the terminals, therebyminimizing the effect on the terminals caused by implementing theMultimedia Ring Back Tone service of video phone.

Since the video phone communication is charged upon detecting that thecalled terminal answers the call (or the establishment of the fourthbearer is completed), the communication duration may be calculated andcontrolled accurately in the implementing process of the Multimedia RingBack Tone service.

The calling terminal is notified to ignore the charging or timing beforedetecting that the called terminal answers the call, and is notified tostart charging or timing upon detecting that the called terminal answersthe call, so that the calling terminal may accurately acquire thecommunication duration calculated on the network side, so as to avoidthe misunderstanding of the user of the calling terminal on the charginginformation.

In the scheme of performing the video phone communication via the fourthbearer, before establishing the fourth bearer of video phone, the thirdbearer established between the calling terminal and the Multimedia RingBack Tone server is to be removed upon detecting that the calledterminal answers the call, so that the circuits occupied by theMultimedia Ring Back Tone server may be released immediately when theuser communication is connected, thereby saving the limited circuitresources.

Although the present invention has been illustrated and described withreference to some preferred embodiments of the present invention, thosewith ordinary skills in the art should be understood that variousmodifications may be made to the present invention in forms and details,without departing from the scope of the present invention.

1. A method for a video phone call, comprising: establishing a first bearer of video phone using H.245 protocol between a calling terminal and a Multimedia Ring Back Tone (MRBT) server; the calling terminal receiving a first H.245 instruction from a Mobile Switching Center (MSC) server corresponding to the calling terminal, wherein the first H.245 instruction is used to indicate the calling terminal to ignore timing the video phone call; the calling terminal receiving a video MRBT via the MRBT server; after the called terminal sending a connect message to a MSC server corresponding to the called terminal, the calling terminal receiving a second H.245 instruction from the MSC server corresponding to the calling terminal, wherein the second H.245 instruction is used to indicate the calling terminal to start timing the video phone call; the calling terminal starting timing of the video phone call according to the second H.245 instruction; performing a video phone communication between the calling terminal and the called terminal via the first bearer and a second bearer of video phone; wherein the second bearer is set up between the called terminal and the MRBT server using H.245 protocol.
 2. The method according to claim 1, wherein before establishing a first bearer of video phone, the method further comprises: the calling terminal receives Alerting message and Connect message sent by the MSC server corresponding to the calling terminal.
 3. The method according to claim 1, wherein the method further comprises: upon detecting the called terminal answers the call, the MSC server corresponding to the calling terminal starts charging the video phone call.
 4. The method according to claim 1, wherein the first H.245 instruction and the second H.245 instruction are H.245 Commands, H.245 Indications, or Dual-tone multi-frequency (DTMF) signal.
 5. The communications device of claim 1, wherein after the called terminal sending the connect message to the MSC server corresponding to the called terminal and before the calling terminal receiving the second H.245 instruction, the method further comprises: the MSC server corresponding to the called terminal sends a Bearer Independent Call Control (BICC) Answer Message to the MRBT server; the MRBT server sends a BICC Answer Message to the MSC server corresponding to the calling terminal, and the MSC server corresponding to the calling terminal starts charging the call. 